DESCRIPTION: The proposed research is designed to develop more effective self-help interventions for smoking cessation. Smoking is the most preventable cause of cancer mortality, but 47 million Americans continue to smoke. Smoking cessation clinics have reached only about 1 percent of eligible smokers. Home based programs that are action-oriented reach only about 1-5 percent. In the current study using stage-matched interventions and proactive recruitment 85 percent of a defined population of smokers in an HMO were reached. It is proposed that this marked increase in participation rates needs to be complimented by dramatic increases in cessation rates of the most promising self-help interventions developed to date. The proposed research is a continuation of 15 years of research on self-change approaches to smoking cessation already funded by NIH. This research program has produced models, measures and intervention methods that are having major impacts on the field. The current project has accomplished all of the aims proposed including unprecedented participation rates, individualized and interactive interventions outperforming self-help manuals at 1, 2 3 and 6 series of contacts; enhanced proactive counselor protocols producing high abstinence rates at 12 months, and a low cost single contact expert system producing relatively high abstinence rates. The proposed extension is a population based clinical trial with 5500 smokers proactively recruited from an HMO and randomly assigned to one of nine conditions varying from low to high contact intensity. These conditions include: 1) no treatment; 2) proactive assessment every six months; 3) single expert system intervention; 4) a matched modality intervention combining the best modality for smokers in each of three stages of change; 5)the investigators most effective three intervention expert system; 6) and 7) enhanced personal choice and professional choice versions of the standard systems; 8) an enhanced proactive counseling condition with counselor fading; and 9) a stepped care population program progressing from expert systems, to counseling and nicotine replacement where indicated. Data analyses will identify the most effective, cost-effective and generalizable elements of these smoking cessation interventions in preparation for dissemination to entire populations. This research is designed to continue the investigators' contributions to cancer control by developing and evaluating stage-matched, interactive and proactive self-help interventions that have the potential to produce unprecedented impacts on entire populations of smokers.